How to execute multiple linux command in parallel from servlet?

I am developing some application in which I have to execute some kind of command with various arguments multiple times. And I also want to execute this commands parallel. I want this commands to get executed from one server. Can anyone please guide me that what is the best way for this kind of problem? How can I execute multiple commands from servlet in back end?

I suggest you find answers to those two questions separately. For all we know you already know the answer to one of them and not the other. So let's start with the first one:

First of all you have to be running your servlet on a Linux machine, because you're going to be executing your command on the machine where the servlet is running. You didn't specify that as one of the requirements, but I'm going to assume that because it's a lot easier. I'm sure you would have mentioned if you wanted to run the command on a different machine. So:

You use ProcessBuilder to run a command. Start with that and get it running first. Run your commands sequentially rather than in parallel first to make sure you have it working reliably.